This invention relates to magnetic recording media such as magnetic disk, magnetic tape, magnetic card, magnetic drum, etc., and more particularly to a magnetic recording medium which comprises a magnetic recording film and a surface treatment layer thereon chemically bonded firmly to the film and which has excellent sliding endurance characteristics and high reliability, a process for producing the magnetic recording medium, and a surface treatment agent for the magnetic recording medium.
Generally, the surface of a magnetic recording medium is rubbed by a magnetic recording head or the like at the times of recording and reproduction. To prevent the reduction in the performance of the magnetic recording medium due to the friction, it is necessary, for instance, to provide a lubricating layer adhered firmly to the magnetic recording film. As a lubricant to be provided on the magnetic recording film, perfluoropolyether is generally known to have relatively good performance. Particularly, a perfluoropolyether having a polar group at a terminal has been proposed as a lubricant which is capable of cleaning with isopropyl alcohol and is highly adhesive to magnetic recording media (U.S. Pat. No. 4,268,556).
Besides, a method of providing a surface treatment layer on a magnetic recording film so as to obtain a higher adhesiveness to a lubricating layer is disclosed in Japanese Patent application Laid-Open (KOKAI) No. 57-164430(1982).
Moreover, in relation to coating magnetic recording media formed by use of a magnetic coating comprising magnetic particles and a binder, there has been proposed a method of providing a surface treatment layer by use of two types of surface treatment agents, one type having a functional group for bonding to the magnetic particles and the other type having a functional group for bonding to the binder [Japanese Patent Application Laid-Open (KOKAI) No. 63-69020(1988)].